1. Field of the Invention
The present invention relates to processes of forming images, in particular an electrophotographic process of forming images, the process comprising a step of applying a lubricant and being capable of forming high-quality images without defects over a long time.
2. Description of Related Art
Electrophotographic imaging apparatuses form toner images on transfer media by repetition of a series of steps, such as charging of photoreceptors, developing of images, and transfer of images. Electrostatic latent image carriers (also referred to as “electrophotographic photoreceptors” or merely “photoreceptors”) included in the electrophotographic imaging apparatuses have residues adhering to their surfaces during the series of steps, such as residual toners not transferred onto transfer media (also referred to as “untransferred toner”), external additives contained in developers, and dust.
To remove such residues, the electrophotographic imaging apparatuses each include a cleaning blade disposed in pressing contact with the surface of the electrostatic latent image carrier to remove these residues, so that the electrophotographic imaging apparatuses can repeatedly form high-quality clear images.
Increasing demands for high-definition high-quality images lead to use of toners having small particle diameters prepared by polymerization, such as dissolution suspension or emulsion polymerization aggregation. These toners having small particle diameters have large adhesive force to the surfaces of electrostatic latent image carriers, and readily remain on their surfaces in the form of residues, such as untransferred toner. If the cleaning blade is pressed against the electrostatic latent image carrier more strongly to remove residues, a large frictional force is generated between the electrostatic latent image carrier and the cleaning blade, and gradually abrades the surface of the electrostatic latent image carrier.
To avoid such wear, an imaging apparatus is disclosed that includes a lubricant applicator to apply a lubricant onto the surface of an electrostatic latent image carrier, for reducing the frictional force between the electrostatic latent image carrier and a cleaning blade to reduce wear of the surface of the electrostatic latent image carrier during removal of residues left on the surface of the electrostatic latent image carrier (for example, see Japanese Patent Application Laid-Open No. 2010-210799).
If a lubricant is unevenly applied onto the surface of the electrostatic latent image carrier, the electrostatic latent image carrier is also unevenly charged. Such uneven charge of the electrostatic latent image carrier causes defects in images.
Accordingly, it is desirable that the lubricant be uniformly applied onto the surface of the electrostatic latent image carrier in a sufficient amount to prevent wear of the surface of the electrostatic latent image carrier.
Unfortunately, the lubricant applicator inevitably causes uneven application of the lubricant during long-term image forming operations, and thus precludes long-term stable formation of images.